Control device for heating systems



Nov. 9, 1937. E. J. DILLMAN CONTROL DEVICE FOR HEATING SYSTEMS Filed April 22, 1935 3 Sheets-Sheet l INVENTOR K 5 0% w ATTORNEY Nov. 9, 1937. E. J. DILLMAN CONTROL DEVICE FOR HEATING SYSTEMS 3 Sheets-Sheet 2 Filed April 22, 1935 m a "v =51:

M ATTORNEY Nov. 9, 1937. J mLLMAN 2,098,912

CONTROL DEVICE FOR HEATING SYSTEMS Filed April 22, 1935 3 Sheets-Sheet 3 INVENTOR I flw/M KM AA) ATTORNEY Patented Nov. 9, 1937 UNITED STATES PATENT OFFICE CONTROL DEVICE FOR HEATING SYSTEMS Application April 22, 1935, Serial No. 17,631

8 Claims.

My invention relates generally to heating systems and more particularly to control devices for such systems.

One of the objects of my invention is to provide 5 a new and improved heating system having provision for controlling both the supplying of heat to the boiler and the supplying of water to the boiler in accordance with Variations in the level of the water in the boiler.

Another object of my invention is to provide new and improved control mechanism for heating systems for controlling the supplying of water to the boiler of asystem and for stopping the supplying of heat to the boiler upon a decrease in is the level of the water therein to a predetermined point or" safety.

Another object of my invention is to provide a control device of the character which is responsive to changes in the liquid level in a liquid container and to provide a device of this character having a new and improved arrangement of the operating parts thereof.

While the invention is capable of wide use for the control of combustion in a heating system and for controlling the supplying of water to the boiler in a system, it will be particularly useful for controlling the combustion of an oil burner or fire stoker applied to a heating system' For example, it may be employed to control a supply of oil, or a supply of air and oil, or other fuel to a burner and to stop such supply when the water level in the boiler decreases below a predetermined point of safety and while the control devices shown are described as being controlled by changes in liquid level in the boiler, it will be understood that devices responsive to boiler pressure 'or temperature could be employed, if desired.

The invention consists in the improvements to be more fully described hereinafter, and the form of the system shown in Fig. 1 and innbodying features of my invention; 50 Figure 3 is an enlarged view shown partly cross-section and partly in elevation of a i device employed in the system of Fig. i bodying features of my invention;

Figure 4 is a view shown in cross section taken. along the line l-d of Fig. and v [Q novelty of which will be particularly pointed out Figure 5 is a view taken in the direction of the arrows 5-5 of Fig. 3.

Referring to the drawings, and more particularly to Fig. 1, there is shown a heating system which includes a boiler l and a heat supplying means therefor which may be a fuel stoker or oil burner preferably operated by an electric motor 2. The system also includes a water supplying means of which only the water feed pipe, indicated at 3, is shown and through which water is supplied to the boiler I when necessary. In the water feed pipe or conduit 3, there is provided a control device 4 for controlling flow of Water to the boiler and also in the feed pipe there may be provided a strainer, indicated at 5 and preferably located, as shown, between the source of water supply and the control device 4. The control device 4 may be of any suitable type, and is referably an electrically operated device, such as, a solenoid valve. In the present instance, the valve of the control device 4 is opened permitting flow of water to the boiler i when the solenoid is energized and closed upon deenergization of the solenoid to stop flow or admittance of water to the boiler. A by-pass pipe 6 is provided in the feed pipe 3 for lay-passing water around the solenoid valve 4 to the boiler i, and flow through the bypass pipe may be controlled by a hand operated valve 6 the purpose of the by-pass being hereafter described.

The heating system also includes a control device, designated generally by the numeral l and which control device is, in the present instance, of the float controlled type. The float, indicated at 8, is operable in response to changes in the level of the water in the boiler l to control the operation of both the burner motor 2 and the water supply control device or valve l. Associated with the float mechanism, there is provided a switch means, designated in general by the letter B and a second switch means designated by the letter C, both of which are controlled or actuated by the float to control. actuation of the solenoid valve 4 and the 1 nor "notor 2, respectively. The burner motor e operated from the usual 11% volt line to re connected primary lead wires ii and vhich there may be provid :l a manural e A control. device, such as es it and i2 and from the relay, lead and connect-the burner motor 2 in ice therewith. The switch means is in series with the burner motor 2 and is oli tively dicated at l l is provided in circuit in to the relay M by means of the lead 5 wires i 5!, l2 and i6 and therefore controls the operation of the motor. The switch means B is operatively connected in parallel circuit with the burner motor 2 by means of a lead wire ll connected to lead wire l2 and a lead wire 68 connected to lead wire it of the switch means 0. In the lead wires ill and it there is preferably provided a transformer is to provide a low voltage current for operating the solenoid valve d. The switch means B has a lead wire connected to the secondary of the transformer is and a lead wire connected'to the solenoid from which a lead wire connects the solenoid to the secondary of the transformer. Thus, since the solenoid is in parallel circuit with the burner motor 2, the solenoid will be deenergized as well as the motor 2 when the circuit is opened to the motor. The numeral 20 designates a room thermostat connected to the relay M to cut, in and cut out the motor 2 to maintain a predetermined room temperature.

In the system shown in Fig. l, the float mechanism and the associated switch means B and C are mounted on a wall of the boiler l with the float ill projecting into the interior of the boiler. Referring now to Figs. 3, 4 and 5 in which the detail construction of the float mechanism and the associated switch means B and C is shown, the structure includes a supporting means in the form of a plate 20 which is fixed to the outer wall of the boiler i by means of bolts or other suitable securing means. The plate it closes an opening in the wall of the boiler 11 provided to receive a casing or housing 23 which projects therethrough into the interior of the boiler and encloses the float t. The casing 23 is constructed, in the pr'sent instance, of sheet metal and comprises a shell or sleevelike member 25 closed at the top by a plate 26 and at the bottom by a second plate 271.

. The sleeve or shell 25 is of substantially U-shaped cross-section, as shown in Fig. 4, and opposite sides of the U-shaped sleeve are formed with outturned flange portions- 28 for bearing against the inner wall of the plate 2i which is preferably recessed as at 29. Screws 3%, or other suitable attaching means, may be used for rigidly securing the casing 23 to the plate M. In a wall of the casing 23 and preferably in a substantially vertical wall ofthe casing there is provided an aperture 32 adjacent the bottom of the casing and a second aperture 33 adjacent the top of the casing for the passage of water in and out of the float casing in accordance with variations in the liquid level of the water in the boiler l. By providing relativelysmall apertures in the casing 23 and by locating them in a vertical or substantially vertical wall of the casing, water will flow in and out of the casing 23 without the transmission of the motion of the surging boiler water to the water within the casing 23 and therefor without transmission of such motion to the float 8.

The plate M is formed with an outwardly extending proturberance 3! which is in alignment with the casing 23 and which has a centrally disposed'opening 32 therethrough opening through the plate 2i into the fioat chamber or interior of the casing 23. Mounted on the outer wall of the plate 2i there is a supporting means in the form of a housing which includes an end wall member or bracket M which may be in the form of a casting, as shown. The supporting means 36 has an end .wall portion 35 disposed toward the end wall of the protuberance 3i, and extending rearwardly from the wall 35 at the top and bottom thereof are oppositely disposed and substantially parallel flanges 3i and 38, the bracket or supporting means M thus having the form of a U-shaped channel member, as shown more clearly in Fig. 4. The U-shaped edges of the ends of the channel-shaped portion are preferably formed around the inner walls with an offset or recessed portion for receiving the oppositely disposed sides of a three-sided closure memberor cover it. The cover lll cooperates with the inner walls of the flanges Stand 38 and the wall 35 to provide a chamber ill and the cover may be secured to the U-shaped channel portion by means of screws.

Through the ,wall 35 of the supporting means 3 3 there is provided an opening 33 in alignment with the opening 32 in the plate 2i, and extending through the aligned opening 33 and 32 and into chamber ll is one end of a lever it, the other end of which is rigidly fixed to the float 8. A movable sealing means is provided for closing and sealing the opening between the chamber M and the boiler l and the sealing means may be of any suitable type, such as a substantially cylindrical, circumferentially corrugated, resilient, metallic bellows till. The bellows ill has one end secured and hermetically sealed to a ring-like end wall member 38, which member is tightly clamped between the outer end wall of the proturberance 3i and an extended portion lil of the wall 35 of the supporting means 36. The outer end wall of the extended portion is recessed providing an outwardly facing annular shoulder or seating surface against which'the ring-like end wall lt of the bellows bears. The outer end wall of the protuberance 3!! is formed with a reduced and extended portion which extends into the recess in the wall 35 and bears against the adjacent side of the ring-like end wall 48 of the bellows ill. The supporting means 3d and the plate member it may be secured together by means of screws 50 and the end wall of the bellows may be tightly clamped therebetween. The bellows ll! surrounds the float arm it and extends into the chamber ll, the inner end being secured and hermetically sealed to a plate 52 which is centrally apertured to receive a reduced portion of the lever M which reduced portion projects through and extends beyond the outer wall of the plate 52'. A shield 53 in the form of a cap member is provided and has a central aperture for receiving the reduced end of the lever it, and the cup-shaped shield 53 surrounds the bellows M and extends toward the wall 35 of the supporting means 3 5.

A yoke or U-shaped bracket 55 is provided and is fixedto the outer end of the lever t6 and within chamber ill. The yoke 55 has a side 56 which extends transverse tothe lever t8 and oppositely disposed arms or flanges 51 which extend on opposite sides of the lever and inwardly or toward the float 8. The side 56 of the lever is provided with an aperture between the oppositely disposed sides or flanges Ell for receiving the reduced portion of the lever M which portion is threaded for threaded engagement with a nut 58 by means of which the yoke, shield and end wall of the bellows may be tightly clamped against the shoulder, formed on the rod by the reduced portion. and thereby be rigidly secured to the end of the lever. 1

On opposite sides of the bellows M are vertically disposed ribs 60 which extend from the wall 35 of the supporting means fi l, rearwardly or into the chamber ll. The ribs 60 are formed with pivotally supporting the yoke 55. In the oppositely disposed sides 51, of the yoke, and ad-- jacent the ends thereof are provided aligned apertures for receiving the pins 62 which pins 5 may be screw-threaded or otherwise suitably fixed to the bosses 6 l. Preferably the pivot pins 62 are located. the same horizonal plane as the longitudinal axis of the lever 46 and bellows ti and preferably a point substantially midway between the ends of the bellows. By locating the pivot point of the lever 55 at a point stantially midway between the ends of the the bellows will bend at their natural "so at upon pivotal movement of the lever t it Mounted on the upper flange of the support e electric 5 tot: means G and the flange 38 is the eans and C are to each have o ei'atio i wit a ransve eiy theretnrougn 1 aa's transverse to the there is a longir thrust member which "projects at -ts ends om the opposite faces of the supporting member ll. The thrust m mber is preferably in the form of a cylinving a conical or pointed end por tion one end portion engages the und rside of the contact carrying arm l5 adiacent its fulcrum so as to swing the arm 15 away from the member I I. The other end. of the thrust member 85 is in alignment with and bears against the end of a rod 86, which rod has one end screw-threaded into or otherwise suitably fixed to a second rod 81, carried by the yoke 55. The rod 8'! has one end bifurcated with the sides thereof extending on opposite sides of one of the arms 55 of the yoke 55 and which may be fixed thereto by means of a rivet S8, or other suitable means. The rod tl' is fixed to the iiange or arm 5? of the yoke at a point between the pivot pins and the transverse connecting side 56. To the other or oppositely disposed flange or arm of the yoke is fixed a rod Gil which eX- tends therefrom and downwardly through the flange into the casing of the switch means B. The switch means has a thrust member like the thrust member $35 of switch means C and which is similarly arranged with the switch mechanism within casing to transmit movemerit of the float to open and/or ermit closing of the switch. For a more detailed description of the sw tch mechanism reference may be had to my sending aioication on electric switches, Serial No. 714,743, filed March 9, 193%.

In Fg. oi the drawings, the normal level of the watei in the boiler i is indicated by the line oelow the normal levei A there are indicated B, C and C which levels the d vices operate as hereafter described. l of the water in the boiler reaches moved onward and it yoke o, of the pivot points, moves e thrust e race of b e magnet opposing the ch. Upon pening the switch ergized and permits the o nst th ereof operates to hold the con-- C together, and thus maintain the circuit closed to the burne motor 2. If for some reason the level of the water in the boiler decrea to the level C", for example, cause iiure of the water su y, because oi" sticle nave descen ts wi Since the solenoid l is parallel the motor it will be seen that the also be deenergzed upon decrease in to level C" so that the valve will be Upon resumption of water e of supply, water is admitted open ng the hand valve in "v" zen the water rises to the level C, the float having moved upward per mits the agnet l of the switch means C close the circuit to the "earner motor 2 and thus resume the supplying of heat to the boiler it, "When the level of t -e water in the boiler reaches level B" then the switch means B is permitted to close the circuit to the solenoid valve 4 which is then moved to open position. Upon resumption of normal operation of the solenoid valve 4, flow of water through the lay-pass line 6 may be discontinued by closing the hand valve t it will be ing of valve in closed position, then the float understood that for all levels above level C the motor 2 is operating to supply heat to the boiler.

with the boiler through a connecting pipe Q41. A

pipe 95 provides communication between the interior of casing 93 and the interior of the boiler, the pipe 95 being connected to the top wall of the boiler or above the normal high level, in the usual manner.

What I claim and desire to secure by Letters Patent of the United States is:

1. In a heating system having a boiler adapted to contain water and a heat supplying means for the boiler, means for supplying Water to the boiler, control means operable upon decrease in the level of the water below a predetermined level for discontinuing the supplying of heat to said boiler, and means controlled by "said control means for preventing the admission of water to said boiler when the level of the water decreases to said predetermined level.

2. In a heating system having a boiler to which water fiows, a float for said boiler operable in response to changes in the level of the water therein, electrically operated means controlling flow of water to said boiler and controlled by said float, said electrically operated means being operable upon a decrease in the level of the water in the boiler to a predetermined level to supply water to the boiler, means for supplying heat to said boiler, and a second electrically operated means for controlling the supplying of heat to said boiler and controlled by said float, said second-named electrically operated means being operable upon a decrease in the level of the water in said boiler below said predetermined level to stop the supply of heat to the boiler, said first-named electrically operated means being in parallel circuit with said second-named electrically operated means and being d-eenergizable when the supply of heat is discontinued for discontinuing the supply of water.

3. In a heating system having a boiler adapted to contain water and a heat supplying means for the boiler, electrically operated means for controlling the supplying of water to said boiler and operable upon decrease of the level of the water in the boiler to a predetermined level to admit i Water to the boiler, a second electrically operated means for controlling the supplying of heat to the boiler and operable upon a decrease in the level of the liquid in said boiler below said predetermined level to stop the supplying of heat to the boiler, a float for the boiler and operable in response to changes in the water level therein, a pivot-a1 arm operated by said float, and a pair of switch means operated by said arm for controlling energiz-ation of said electrically operated control means, one of said switch means being operable to control both of said electrically operated means upon decrease in liquid level to said second-named predetermined level.

boiler, means operable upon variations in the level of the water in the boiler to control the supplying of water thereto, and means operable upon a decrease in the level of the water to a predetermined level to discontinue the supplying of heat and the supplying of water to the boiler.

6. In a heating system having a boiler adapted to contain water and a heating means for the boiler, means for supplying Water to the boiler, an electrically operated control device responsive tovariations in the level of the water in the boiler for controlling the supplying of water thereto, and a second electrically operated control device in parallel circuit with said first-named control device and controlling said heat supplying means, said second-named control device being operable upon a decrease in the level of the water in the boiler to a predetermined level to stop the supplying of heat to the boiler andto deenergize said first-named control device to stop flow of water to the boiler.

7. In a heating system having a boiler for containing water and a heat supplying means therefor, means for supplying water to said boiler, means for controlling the supplying of water to said boiler, means operable within predetermined liquid levels for normally controlling said control means, and means operable upon a decrease in the level of the liquid to a predetermined level below said first-named predetermined levels for discontinuing both the supplying of heat and the supplying of water to said boiler.

8. "In a heating system having a boiler for containing water and a heat supplying means therefor, means for supplying water to said boiler, a float operable in response to changes in liquid level in said boiler, and a switch means operable by said float upon decrease in the level of the water to a predetermined level for discontinuing both the supplying of heat and the supplying of water to said boiler.

EARNEST J. DILLMAN. 

